Balance sheet components - Schedule Of Accounts Notes Loans And Financing Receivable (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Trade Receivables	$ 25,790	$ 11,085
Other Receivables	951	1,313
Allowance for Doubtful Accounts	(365)	(294)
Accounts receivable, net	$ 26,376	$ 12,104

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant